Bergey 24 VDC B, Owner'S Manual

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which allows the turbine to run unloaded.  Under 
unloaded operation the rotor will spin faster and it 
will make more noise.  In high winds the blades 
may also “flutter”, causing a loud, low pitch growl-
ing sound. 
 
The AutoFurl system works whether the turbine is 
loaded or unloaded.  Applying extra loads during 
high wind periods can reduce the likelihood of 
blade flutter. 
 

D.  PowerCenter Controller 

 
The basic electrical schematic for the BWC XL.1 
is shown in Figure 5.  The XL.1’s alternator pro-
duces three-phase alternating current (AC) that 
varies in voltage and frequency with the rotor 
speed.  The AC power is rectified to direct current 
(DC) power by a rectifier module inside the na-
celle.  Thus, the wire run from the wind turbine to 
the PowerCenter is DC. 
 

Alternator

Rectifier

(on turbine)

DC Wire Run

PowerCenter

Figure 5, XL.1 Basic Electrical Schematic

 
The PowerCenter for the XL.1 has two sets of 
color-coded light-emitting-diodes (LED’s) for Sys-
tem Status and Battery Bank Status. 
 

System Status Lights: 

Solar Power

 (green):  Lights up when the op-

tional solar panel(s) are charging the batteries. 
 

Extra Load

 (red):  Lights up when the optional 

auxiliary or dump load is activated due to high 
battery voltage. 
 

Wind Power

 (green):  Lights up when the XL.1 

wind turbine is charging the batteries.  
 

Power Boost

 (green):  Lights up in low to 

moderate winds to indicate that the low wind 
speed performance optimizing boost circuitry is 
operating. 

Battery Bank Status Lights: 

 
Battery bank charge status is shown with ten col-
ored LED’s, which act like a fuel gage for the re-
mote power system.  This gage, however, is inex-
act and it is intended to provide only a general 
indication of the energy reserves available in the 
system.  The following table shows the voltage 
indicated by the highest lit LED and its approxi-
mate relationship to the battery capacity available. 
 

LED No. 

(from left 

side) 

Indicated 

Battery 

Voltage 

Range 

Approxi-

mate Bat-

tery Re-

serve 

L1 (red) 

Below 22 V 

Below 5% 

L2 (yellow) 

22 – 23.5 V 

5% 

L3 (green) 

23.5 – 24 V 

15% 

L4 (green) 

24 – 24.5 V 

30% 

L5 (green) 

24.5 – 25 V 

60% 

L6 (green) 

25 – 27 V 

90% 

L7 (green) 

27 – 28 V 

100% 

L8 (green) 

28 – 29.5 V 

100% 

L9 (yellow) 

29.5 – 30.5 V 

100% 

L10 (red) 

Above 30.5 V 

100% 

       Table 1, Battery Bank Status Indications 

 
The LED’s provide an indication of the instanta-
neous battery voltage.  This voltage is affected by 
the state of battery charge and the instantaneous 
net current flow into or out of the battery.  There-
fore, during high charging/low load periods the 
gage will over-predict battery state of charge and 
during low charging/high load periods the gage 
will under-predict battery state of charge.  Also, 
the smaller the battery bank the more rapidly the 
LED’s will change in response to changing wind 
and electrical load conditions. 
 
The PowerCenter is designed to work with 
flooded-cell or sealed, deep-cycle, lead-acid bat-
teries.  Do not use other types of batteries without 
first contacting Bergey Windpower Co. 
 

Battery Equalization 

 
The PowerCenter has an automatic one-hour bat-
tery equalization function that is initiated using the 
push button on the back side of the PowerCenter 
enclosure.  Equalization is a maintenance function 
that brings the batteries up to a higher state of 
charge and causes them to out-gas (bubble) ac-